Piano-player mechanism.



W. T. WAITE. PIANO PLAYER MEGHANISM. APPLIOATION FILED AUG. 29, 1913.

Patented Dec. 8, 1914.

WILLIAM T. WAITE, OF LAPORTE, INDIANA, ASSIGNOR TO THE ORPHEOLA COMPANY,

OF LAPORTE, INDIANA, A CGRPORATIN 0F INDIANA.

PIANO-PLAYER MECHANISM.

Application filed August 29, 1913.

To all whom t may concern Be it known that I, VILLIAM T. WAITE, a citizen of the United States, residin at aporte, in the county of Laporte and State of Indiana, have invented certain new and useful Improvements in Piano-Player Mechanisms, of which the following is a specification.

This invention relates in general to piano player' mechanisms and more particularly to the valves which control the operation of the hammer actuating pneumatics.

curately control the operation of a piano hammer, and more specifically its object is to provide a simple and efficient guide for maintaining said valve in proper operative position and which can be produced at low cost.

In the accompanying drawings, Figure 1 is a transverse sectional view of the pneumatic of a piano player mechanism embodying my invention; Fig. 2 is a transverse setional view of the upper or valve bar; Fior. 3 is a detailed longitudinal section of the same, and Figs. l and 5 are top and bottom plan views, respectively, of the same.

Referring to the drawings, 9 is the vacuum chest, l0 the bottom bar and 11 the upper or valve bar. The bottom bar is provided with channels 12 communicating with tubes 13 which lead to the openings in the traclrer bar (not shown). Each channel 12 also communicates with a diaphragm chamber 14. A sheet of suitable material is secured on the bottom bar to form a flexible diaphragm 15 above each diaphragm chamber 14 and each of said chambers has a bleed or vent opening 16 normally closed by a pin 17.

A bellows or pneumatic 18 is fastened to the bottom bar 10 opposite each diaphragm 21 in the bottom bar and the passages 22 and 23 in the upper or valve bar 11 with the valve chamber 24 in the upper bar. The diaphragm chambers are arranged in staggered relation and the valve chambers are similarly arranged immediately above the diaphragm chambers. A strip 32 is fastened to the upper or valve bar 11 and is provided Specification of Letters Patent.

Patented Dec. 8, 1914. Serial No. 787,295.

with a port 34 above each valve chamber for t e a ission of air through the valve cha1nber, passages 23, 22 and 21 and opening 19 to the bellows.

The underside of the upper or valve bar 1 is provided with alternate ribs 26 and grooves 26 extending longitudinally thereof and the valve opening or passage 27 to each valve chamber in the ar is annular in shape and intersects two adjacent grooves. A cylindrical core l-l located in the valve opening 27 is integral with the rib 26 between the two grooves 26', which are intersected by said valve opening, and this core has a central bore 28 and forms the guide for the valve.

The valve 31'is provided with a stem 29 which projects downward through the bore immediately above the diaphragm chamber. his valve normally closes the opening 27 and is adapted to be lifted by the diaphragm to open said opening 27 and close the port prefer to provide the opening 27 and the port 34: with thimbles 36 and 38, respectively, to furnish smooth and proper seats for the valve and l also prefer to provide the valve with a suitable facing on its upper and lower sides to engage the valve seats. While the stem may be connected to the valve in any suitable manner, I have shown it provided with an enlarged head 39 located in a depression in the valve above the facing on the lower side thereof.

A pin 42 threaded through carries at its lower end a ment 4-3 which is positioned in the vacuum chest 9 above the diaphragm and preferably over the bleed opening therein. This pin to permit adjustment of the stop to the requisite position. This stop serves to regulate the flow of air through the bleed opening and is preferably so adjusted as to partially obstruct the bleed opening while the diaphragm is in elevated position and thus permit the diaphragm to be held in elevated position without imposing unnecessary duty upon the means provided to exhaust the air in the vacuum chamber. It is not thought that event the diaphragm might stick to the aperture in the note sheet passes out of registration With the aperture in the tracker board.

In the practical operation of the mecha` nism air is exhausted from the vacuum chest 9, and from the channels 12 and tubes 13, through the bleed or vent openings 16 in the usual Way and the diaphragms are seat.- ed by the valve stems Q9 under the pressure of atmospheric air upon the valves 31. When air is admitted by the note sheet through a tube 13 and channel 12 to the diaphragm chamber, the diaphragm is lifted, thereby lii'ting the valve 31 against the inlet port 34: to permit lthe air in the bellows 18 to escape through opening 9, passages 21, 22 and 23, into the valve chamber and thence through the valve opening into the vacuum chamber, to thereby close the pneumatic 18 and operate the abstract'through the finger 25. When the note sheet closes the opening in thetracker bar, the air in the tube 13 and channel 12 escapes through the bleed or vent opening in the diaphragm into the vacuum chamber and the diaphragm seats itseli, at the same time permitting the valve 31 to lclose the valve opening, thereby opening the port 3% and admitting atmosheric air to the bellows.

By employing a single valve for control- Copies of this patent may be obtained for five cents each, by addressing the Washington, D. C.

air from the bellows to er and the inlet of atling the Outlet o' the vacuum Chamb mospheric air to mechanism of very simple construction, which is extremely accurate and sensitive in operation and by utilizing a portion of the upper or valve bar 11 to constitute the guide i1 for the valve stem I not only `reduce the cost of manufacture to a minimum, but also provide a superior and eiiicient guide for the valve stem.

I claim: In a piano player mechanism, the combination oi' a vacuum chest, a chamber having an opening to the atmosphere, above said vacuum chest and separated therefrom by a rigid partition, said partition being groove on its under side to provide a rib and grooved lon its upper side to provide a cylindrical core'surrounded by an annular passage communicating With the grooves on the under side, a single valve disk disposed in said chamber adapted to alternately close said passage and said opening and having a stem disposed through said core and rib, and means for actuating sai valve.

y Y Y WILLIAM T. WAITE. Witnesses WALTER F. HANsCHILD, EDWIN W. SGHURZ Commissioner of Patents,

the bellows I provide aV 

